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    <title>basic_datagram_socket::async_receive_from (1 of 2 overloads)</title>
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            <div><h5 class="title">
                <a name="asio.reference.basic_datagram_socket.async_receive_from.overload1"></a><a class="link"
                                                                                                   href="overload1.html"
                                                                                                   title="basic_datagram_socket::async_receive_from (1 of 2 overloads)">basic_datagram_socket::async_receive_from
                (1 of 2 overloads)</a>
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    <p>
        Start an asynchronous receive.
    </p>
    <pre class="programlisting"><span class="keyword">template</span><span class="special">&lt;</span>
    <span class="keyword">typename</span> <a class="link" href="../../MutableBufferSequence.html"
                                             title="Mutable buffer sequence requirements">MutableBufferSequence</a><span
                class="special">,</span>
    <span class="keyword">typename</span> <a class="link" href="../../ReadToken.html" title="Read token requirements">ReadToken</a> <span
                class="special">=</span> <a class="link"
                                            href="../../asynchronous_operations.html#asio.reference.asynchronous_operations.default_completion_tokens"><span
                class="emphasis"><em>DEFAULT</em></span></a><span class="special">&gt;</span>
<a class="link"
   href="../../asynchronous_operations.html#asio.reference.asynchronous_operations.automatic_deduction_of_initiating_function_return_type"><span
        class="emphasis"><em>DEDUCED</em></span></a> <span class="identifier">async_receive_from</span><span
                class="special">(</span>
    <span class="keyword">const</span> <span class="identifier">MutableBufferSequence</span> <span
                class="special">&amp;</span> <span class="identifier">buffers</span><span class="special">,</span>
    <span class="identifier">endpoint_type</span> <span class="special">&amp;</span> <span class="identifier">sender_endpoint</span><span
                class="special">,</span>
    <span class="identifier">ReadToken</span> <span class="special">&amp;&amp;</span> <span
                class="identifier">token</span> <span class="special">=</span> <a class="link"
                                                                                  href="../../asynchronous_operations.html#asio.reference.asynchronous_operations.default_completion_tokens"><span
                class="emphasis"><em>DEFAULT</em></span></a><span class="special">);</span>
</pre>
    <p>
        This function is used to asynchronously receive a datagram. It is an
        initiating function for an <a class="link" href="../../../overview/model/async_ops.html"
                                      title="Asynchronous Operations">asynchronous
        operation</a>, and always returns immediately.
    </p>
    <h6>
        <a name="asio.reference.basic_datagram_socket.async_receive_from.overload1.h0"></a>
        <span><a name="asio.reference.basic_datagram_socket.async_receive_from.overload1.parameters"></a></span><a
            class="link"
            href="overload1.html#asio.reference.basic_datagram_socket.async_receive_from.overload1.parameters">Parameters</a>
    </h6>
    <div class="variablelist">
        <p class="title"><b></b></p>
        <dl>
            <dt><span class="term">buffers</span></dt>
            <dd><p>
                One or more buffers into which the data will be received. Although
                the buffers object may be copied as necessary, ownership of the
                underlying memory blocks is retained by the caller, which must
                guarantee that they remain valid until the completion handler is
                called.
            </p></dd>
            <dt><span class="term">sender_endpoint</span></dt>
            <dd><p>
                An endpoint object that receives the endpoint of the remote sender
                of the datagram. Ownership of the sender_endpoint object is retained
                by the caller, which must guarantee that it is valid until the
                completion handler is called.
            </p></dd>
            <dt><span class="term">token</span></dt>
            <dd>
                <p>
                    The <a class="link" href="../../../overview/model/completion_tokens.html" title="Completion Tokens">completion
                    token</a> that will be used to produce a completion handler,
                    which will be called when the receive completes. Potential completion
                    tokens include <a class="link" href="../../use_future.html" title="use_future"><code
                        class="computeroutput"><span class="identifier">use_future</span></code></a>, <a class="link"
                                                                                                         href="../../use_awaitable.html"
                                                                                                         title="use_awaitable"><code
                        class="computeroutput"><span class="identifier">use_awaitable</span></code></a>, <a class="link"
                                                                                                            href="../../yield_context.html"
                                                                                                            title="yield_context"><code
                        class="computeroutput"><span class="identifier">yield_context</span></code></a>, or a function
                    object with the correct completion signature. The function signature
                    of the completion handler must be:
                </p>
                <pre class="programlisting"><span class="keyword">void</span> <span
                        class="identifier">handler</span><span class="special">(</span>
  <span class="keyword">const</span> <span class="identifier">asio</span><span class="special">::</span><span
                            class="identifier">error_code</span><span class="special">&amp;</span> <span
                            class="identifier">error</span><span class="special">,</span> <span class="comment">// Result of operation.</span>
  <span class="identifier">std</span><span class="special">::</span><span class="identifier">size_t</span> <span
                            class="identifier">bytes_transferred</span> <span class="comment">// Number of bytes received.</span>
<span class="special">);</span>
</pre>
                <p>
                    Regardless of whether the asynchronous operation completes immediately
                    or not, the completion handler will not be invoked from within
                    this function. On immediate completion, invocation of the handler
                    will be performed in a manner equivalent to using <a class="link" href="../../post.html"
                                                                         title="post"><code class="computeroutput"><span
                        class="identifier">post</span></code></a>.
                </p>
            </dd>
        </dl>
    </div>
    <h6>
        <a name="asio.reference.basic_datagram_socket.async_receive_from.overload1.h1"></a>
        <span><a
                name="asio.reference.basic_datagram_socket.async_receive_from.overload1.completion_signature"></a></span><a
            class="link"
            href="overload1.html#asio.reference.basic_datagram_socket.async_receive_from.overload1.completion_signature">Completion
        Signature</a>
    </h6>
    <pre class="programlisting"><span class="keyword">void</span><span class="special">(</span><span class="identifier">asio</span><span
            class="special">::</span><span class="identifier">error_code</span><span class="special">,</span> <span
            class="identifier">std</span><span class="special">::</span><span class="identifier">size_t</span><span
            class="special">)</span>
</pre>
    <h6>
        <a name="asio.reference.basic_datagram_socket.async_receive_from.overload1.h2"></a>
        <span><a name="asio.reference.basic_datagram_socket.async_receive_from.overload1.example"></a></span><a
            class="link"
            href="overload1.html#asio.reference.basic_datagram_socket.async_receive_from.overload1.example">Example</a>
    </h6>
    <p>
        To receive into a single data buffer use the <a class="link" href="../../buffer.html" title="buffer"><code
            class="computeroutput"><span class="identifier">buffer</span></code></a> function as follows:
    </p>
    <pre class="programlisting"><span class="identifier">socket</span><span class="special">.</span><span
            class="identifier">async_receive_from</span><span class="special">(</span>
    <span class="identifier">asio</span><span class="special">::</span><span class="identifier">buffer</span><span
                class="special">(</span><span class="identifier">data</span><span class="special">,</span> <span
                class="identifier">size</span><span class="special">),</span> <span
                class="identifier">sender_endpoint</span><span class="special">,</span> <span
                class="identifier">handler</span><span class="special">);</span>
</pre>
    <p>
        See the <a class="link" href="../../buffer.html" title="buffer"><code class="computeroutput"><span
            class="identifier">buffer</span></code></a>
        documentation for information on receiving into multiple buffers in one
        go, and how to use it with arrays, boost::array or std::vector.
    </p>
    <h6>
        <a name="asio.reference.basic_datagram_socket.async_receive_from.overload1.h3"></a>
        <span><a
                name="asio.reference.basic_datagram_socket.async_receive_from.overload1.per_operation_cancellation"></a></span><a
            class="link"
            href="overload1.html#asio.reference.basic_datagram_socket.async_receive_from.overload1.per_operation_cancellation">Per-Operation
        Cancellation</a>
    </h6>
    <p>
        On POSIX or Windows operating systems, this asynchronous operation supports
        cancellation for the following <a class="link" href="../../cancellation_type.html"
                                          title="cancellation_type"><code class="computeroutput"><span
            class="identifier">cancellation_type</span></code></a> values:
    </p>
    <div class="itemizedlist">
        <ul class="itemizedlist" type="disc">
            <li class="listitem">
                <code class="computeroutput"><span class="identifier">cancellation_type</span><span
                        class="special">::</span><span class="identifier">terminal</span></code>
            </li>
            <li class="listitem">
                <code class="computeroutput"><span class="identifier">cancellation_type</span><span
                        class="special">::</span><span class="identifier">partial</span></code>
            </li>
            <li class="listitem">
                <code class="computeroutput"><span class="identifier">cancellation_type</span><span
                        class="special">::</span><span class="identifier">total</span></code>
            </li>
        </ul>
    </div>
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